An alternative comparison report provides information about the damage reduced between the without-project condition and with-project conditions. The information about damage reduced is available for both damage measures (expected annual damage and average annual equivalent damage). Four reports are available: damage with uncertainty, damage by impact area, damage by damage category, and a summary report. In what follows, we'll refer to "damage" generally, which should be taken to represent either expected annual damage or average equivalent damage. The reports are equivalent for either measure, except that expected annual damage reports will reflect either the base year or the most likely future year. All compute algorithms in HEC-FDA Version 2.0 are the same as those found in HEC-FDA Version 1.4.3, except those identified in the HEC-FDA Version 2.0 Release Notes.

Damage with Uncertainty 

The distribution of damage reduced is a function of the distribution of with-project damage and the distribution of without-project damage. On the top left-hand corner of the report, mean damage reduced is displayed, underneath which a table of the first, second, and third quartiles of the damage reduced distribution are displayed. On the right-hand side of the report, the distribution of damage reduced is displayed. 

Below is a screenshot of AAEQ damages reduced across all damage categories and impact areas.

Below is a screenshot of EAD reduced across all damage categories and impact areas for the base year condition.

Damage by Impact Area 

The damage by impact area report displays the mean AAEQ damages or EAD reduced for each impact area between the without-project condition and the selected with-project condition. 

Below is a screenshot of EAD reduced across all damage categories by impact area for the base year condition. The same report can be displayed for AAEQ.

Damage by Damage Category 

The damage by damage category report displays mean average annual equivalent damage reduced for each damage category, summed across all impact areas, for the selected with-project condition. 

Below is a screenshot of EAD reduced across all impact areas by damage category for the base year condition. The same report can be displayed for AAEQ.

Summary Report

The summary report displays a comparison of the damage distributions between the without-project condition and each with-project condition. The report shows EAD for the base and future years, as well as the AAEQ. Without project damages, with project damages, mean EAD reduced, and the damages reduced quantiles are displayed.